NATHAN Vardy has revealed the extraordinary range of setbacks that have sidelined him for the past 18 months.

The 24-year-old big man has not played a game at any level since lining up in against Collingwood in the 2014 NAB Challenge.

He has been grounded since suffering a serious knee injury during a competitive training drill the following week.

Vardy would probably have been back on the park some months ago if he had not reinjured the knee in unlikely circumstances.

The setback in question occurred when he fell over after fainting at Daniel Menzel's house following a tough training session during the summer.

He knocked his knee when he fell "and crunched off a big bit of bone".

"I tried to get back from that ... hoping that would get better," Vardy told CatsTV after completing Wednesday's main training session and being cleared to line up in Saturday's VFL game against Essendon at Simonds Stadium.

"But I ended up having to go in for another scope, a cleanout - a bit of bone and scar tissue and that sort of stuff that was going on in there.

"That was obviously very frustrating."

To watch the full interview with Nathan Vardy click on the video player at the top of the page